This invention relates to a method of manufacturing a semiconductor device having a cylindrical electrode.
A recent technical development has brought about a semiconductor device which is capable of providing various electric parts, such as a dynamic random access memory (DRAM) and others.
A conventional DRAM comprises a plurality of stacked capacitors. In the manner known in the art, each of stacked capacitors includes a cylindrical electrode.
Such a cylindrical electrode can be made in the method which will be described in the following. At first, a support member or a block is made of a silicon oxide on a semiconductor tip. Next, the support member is covered with an electrode-forming film which is made of one of a conductive material and a semiconductive material. Thereafter, the electrode-forming film is applied with anisotropic etching known in the art. As a result, the electrode-forming film is partially deleted to form the cylindrical electrode. Such a method is disclosed in a paper contributed by K. Iguchi et al to 1991 Symposium on VLSI Technology, Technical Digest, page 11 and will later be described in detail with reference to the drawing.
In the above-mentioned method, the support member has a side surface which is also etched during the anisotropic etching. Accordingly, the cylindrical electrode has a thickness which inevitably becomes thin. This results in reduction of the electrode's mechanical strength. In the worst case, the entire surface is etched away and consequently no cylindrical electrode is formed at all.